Loy Krathong
Loy Krathong is a traditional Thai festival that is celebrated annually and is also known as the ‘festival of lights’.
The date of the festival is marked by the appearance of the full moon, which means that the times vary every year. However, as a general guide, Loy Krathong is held in November.
source: https://www.chiangmaitravelhub.com/events/loy-krathong/